Clinical History. Mercury In a Home. The Index Case. Lab and Diagnostic Tests. Results

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1 Mercury In a Home Larry K. Lowry, Ph.D Debra C. Cherry, M.D,. M.S. The University of Texas Health Center at Tyler Larissa Velez, M.D. North Texas Poison Center, Dallas Supported by ATSDR and EPA through a cooperative agreement with the AOEC Clinical History In 10/1999, a family of 7 moved to a trailer A plastic container of metallic mercury was found Mercury spilled on carpet The family did not realize Hg was toxic Family did not realize trailer was contaminated with mercury The Index Case 3 y/o Female saw local physician several times between 12/99 and 6/2000 flu-like symptoms, screaming, anorexia, weight loss, and inability to talk. She was hospitalized 6/20/2000 Initial findings by pediatrician Thin, ataxic, not speaking, drooling, hypotonic, tremor Lab and Diagnostic Tests CT of brain, MRI, EEG Ultrasound of abdomen, GI series CBC, Chem Panel, U/A, ESR Blood, urine and spinal cultures Blood levels of heavy metals Results All tests normal on 6/20/2000 except Blood Mercury 29.5 µg/dl (normal < 3) Referred to nephrologist Contacted North Texas Poison Center Obtained 24-hr urine Initial HgU 1097 g/day (normal < 15) Follow up Action Recommended by the North Texas Poison Center 6/26/00 Obtained urine Hg from family members Ordered DMSA chelation for index case Subsequently ordered chelation for all 7/3/00 - Index case discharged Condition much improved 8/00-2nd round of chelation, all 8/1-8/11/00-2nd round of urine collections 10/26/00-3rd round of urine collections 1

2 Laboratory results, HgU Lab results expressed as µg/24 hours. How complete is a 24 hr collection? Guidelines based on µg/l or µg/g creatinine Interpretation difficult especially in the five children ranging from 3-16 years old. Laboratory reported normals as < 15 µg/day. BEI - 35 µg/g creatinine for a spot urine Other family members asymptomatic Urine Mercury, g/day (Normal < 15 g/day) Patient 6/26/00 8/15/00 10/26/00 3 y/o F y/o M y/o F y/o M y/o F y/o F y/o F Laboratory Issues Samples done at Mayo Clinic No external quality assurance program for Hg Internal QA data not available Wrong units for reporting Environmental History 6/26/00 - Family moves to Ronald McDonald Center 6-26/00-6/30 - Identify appropriate agency, TDH Toxic Substances Division TDH Promises to send out IH to investigate 7/3/00 - Family moves in with uncle Decontamination of Trailer, 7/28 Mercury Badge Front Rear Owner gets colorimetric badges to test house Initial tests are high (no collection time noted) Hazmat team decontaminates trailer Remove carpet, couch, some chairs Owner tests trailer 2-days later with badges Results are OK (no collection time noted) Note: detection limits mg/m 3 /hr TLV-TWA for 8-hrs is mg/ m 3 2

3 Interpretation Design is an indicator behind selected filters on front Should see gradation of colors Highest concentration with color change Defective lot, interpretation impossible Follow-up Action 7/28/00 - The family moved back in 9/22/00 IH from TDH visits trailer Takes measurements with Jerome Sniffer. Advises family that trailer is safe Recommends additional cleanup Hg in Air, Jerome Model 411 Location Elevation mg/m 3 Hall Floor Entry to Bed Room Living Room Floor ft above floor Reference Values ACGIH TLV mg/m 3 8-hr TWA TDH mg/m 3 WHO mg/m 3 EPA (ambient air) mg/m 3 Recommendations and Current Status TDH IH advised family to clean the walls with soap and water, put a coating over the floor, and ventilate the home for a month. The index case is now symptom-free. Mercury levels in all family members have dropped considerably. Apparent continuing low-level Hg contamination Lessons Learned Family at risk for 8 months This case illustrates the need for primary care professionals, occupational health specialists, toxicologists, and industrial hygienists to work together and have an action plan to address environmental health problems. 3

4 Resources - Help! The Pediatric Environmental Health Specialty Units Contacts swcpeh@uthct.edu Fax: Region VI Nationwide (903) Web page Southwest Center for Pediatric Environmental Health Goals Bridging the gap between the pediatric health care provider and environmental health specialist to serve children impacted by environmental exposures to potentially toxic agents. Our Mission Develop and present educational programs to pediatric health care providers and public health officials; Provide telephone consultation to health care professionals & public health officials; Provide telephone consultation to the general public. SW-CPEH Involvement Contacted 9/1/2000 with questions on reporting units & interpretation of HgU data Results reported by lab as µg/day, µg/sample or µg/24 hours Provided guidance: units should be µg/l or µg/g creatinine Provided guidelines and report on 9/19/2000 Continued informal collaboration 4

5 Thank you Your questions please 5